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Rails “validates_uniqueness_of” Case Sensitivity
... 3rd Edition:
...despite its name, validates_uniqueness_of doesn’t really guarantee that column values will be unique. All it can do is verify that no column has the same value as that in the record being validated at the time the validation is performed. It’s possible for two records to be ...
Difference between Document-based and Key/Value-based databases?
...e debate on the correct name for databases such as Cassandra, I'd like to call them column-family stores. Although key-value pairs are an essential part of Cassandra, it's not limited to just that. It allows you to nest key-value pairs, so a key could refer to multiple sub-key-value pairs.
You cann...
Xcode 4 and Core Data: How to enable SQL Debugging
...tween 1 and 4, higher number makes it more verbose)
Press OK and your are all set.
The key here is to edit the scheme you will be using for testing.
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How can I get the full object in Node.js's console.log(), rather than '[Object]'?
...console.log(obj) it still prints [Object] for deeply nested objects :( I really wish it would behave as you describe.
– SSH This
Feb 23 '16 at 22:36
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How to write a JSON file in C#?
...ializeObject(_data.ToArray());
//write string to file
System.IO.File.WriteAllText(@"D:\path.txt", json);
Or the slightly more efficient version of the above code (doesn't use a string as a buffer):
//open file stream
using (StreamWriter file = File.CreateText(@"D:\path.txt"))
{
JsonSerializ...
When should you use 'friend' in C++?
...ough the C++ FAQ and was curious about the friend declaration. I personally have never used it, however I am interested in exploring the language.
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What is the correct SQL type to store a .Net Timespan with values > 24:00:00?
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There isn't a direct equivalent. Just store it numerically, e.g. number of seconds or something appropriate to your required accuracy.
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“continue” in cursor.forEach()
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Each iteration of the forEach() will call the function that you have supplied. To stop further processing within any given iteration (and continue with the next item) you just have to return from the function at the appropriate point:
elementsCollection.forEach(...
Vagrant stuck connection timeout retrying
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I really didn't understand what this does, but it worked. So thank you.
– Lavixu
Aug 16 '14 at 4:05
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How to get Latitude and Longitude of the mobile device in android?
... location.getLongitude();
double latitude = location.getLatitude();
The call to getLastKnownLocation() doesn't block - which means it will return null if no position is currently available - so you probably want to have a look at passing a LocationListener to the requestLocationUpdates() method in...